Tre-Owen House was built c.1623, though the original house was 15th century. It is faced in ashlar and there are 4 light stone mullion and transom windows with continuous drip moulds. The 2-storey gabled porch has Jacobean classical enrichment and a Herbert Coat-of-Arms. At the back the house rises to greater height and has 4 storeys. The ground floor rooms are 17' high. There is an oak panelled room with plaster ceiling and Jacobean fireplace and a superb staircase to full height. The north side has 4 tall gables and a stone slate roof.

(Source: Listed Building Record Sheet at 11/05/2000) S Garfi 13/9/06

There are traces of gardens to the north and south of the house (Nprn79027).

[Additional:]

Treowen is of outstanding interest both in terms of plan and surviving detail. It is an early example of a double-pile plan. The arrangement of rooms is still sub-medieval with service rooms on one side of the cross-passage and principal rooms on the other side. The parlour is in the rear pile and originally reached via a doorway (now blocked) off the upper end of the hall. The architectural detail is an instructive repertoire of early C17th detail in stone, timber and plaster. The detail is essentially variations on the ovolo moulding with occasional ogee stops. The plasterwork is of great interest. The principal feature is the pendant ceiling in the great chamber over the hall. This has been damaged but apparently was the model for the reproduction ceiling in Drybridge House. Elsewhere, decorative motifs have been applied to the corners of the ceilings of the principal chambers: fleurs-de-lis, floral sprays, and vine trails. These motifs are found in other houses locally, e.g. St James House, Monmouth. The principal framed stair is the 'great glory' of Treowen and an unadorned example of the turner's craft 'in its heroic infancy' (Girouard). The secondary stair is a splendid mast (pillar) stair.

Several revisions need to be made to the excellent account by John Newman in 'The Buildings of Wales: Gwent/Monmouthshire' (2002). The Jacobean hall screen dated 1627 has been returned to Treowen from Llanarth Court. An internal porch has been reinstated in the parlour from fragments found in the attic. Some fireplaces have been restored, including the hall fireplace, where the lintel had split and was removed. There are numerous unobtrusive and successful repairs.

The raised garden walk (belvedere) enclosing a sunken garden with central mulberry has been restored immediately N of the house. The belvedere gives views to the orchard (N ) and E across to the lakes or fishponds. The lakes belong to a phase of landscape management broadly contemporary with the house and C17th artefacts (including a tig) have been found during dredging. A brick clamp (coal fired) has been found adjacent to the lakes; apparently the lake silt made good bricks.

Information from John and Dick Wheelock. R.F.Suggett/RCAHMW/26 July 2017